Cable unit for connecting devices to enable wireless exchange of data and/or power between them

ABSTRACT

The present invention relates to a cable unit for connecting devices in a system, in particular in a patient monitoring system, to enable wireless exchange of data and/or power between them. The proposed cable unit comprises a cable ( 510 ) and a connector ( 520, 530 ) arranged at each end of said cable, said connector comprising a data transmission unit ( 522, 532 ) for transmitting data to and/or receiving data from a device having a counterpart connector and a magnetic coupling unit ( 521, 531 ) for transmitting power to and/or receiving power from another device of the system having a counterpart connector by use of inductive coupling.

CROSS-REFERENCE TO PRIOR APPLICATIONS

This application is a continuation application of U.S. National Phaseapplication under 35 U.S.C. § 371, Ser. No. 15/748,260, filed on Jan.29, 2018, which claims the benefit of International Application SerialNo. PCT/EP2016/070145, filed on Aug. 26, 2016, which claims the benefitof European Application Serial No. 15183596.4, filed on Sep. 3, 2015.These applications are hereby incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to a cable unit for connecting devices ina system, in particular in a patient monitoring system, to enablewireless exchange of data and/or power between them.

BACKGROUND OF THE INVENTION

Wireless charging or powering of devices in general is an establishedtechnique that is convenient to users. Wireless powering can also beused in harsh environments where corrosion or moisture might jeopardizefunctionality or safety when galvanic contacts are used. There areseveral standards for wireless power such as Qi, PMA, Rezense andWiPower, and the market is growing rapidly. These techniques are mostlyused for charging a battery powered device (e.g. a mobile phone, atablet computer, etc.). Charging of multiple devices is possible. Forinstance in the Qi standard power plates with many smaller coils areavailable, however the devices need to be precisely positioned adjacentto each other (in the horizontal plane).

High-end patient monitoring is expanding from its traditionalapplication in the critical care arena (ICU, OR) towards lower acuitysettings such as the general ward, hospital-to-home, connected primarycare, etc. The success of the existing high-end products is due to thequality of the measurements, their modularity, the overall systemconnectivity, the user interface and its consistency (backwardscompatibility) across the total product line. At the same time the valuesegment market is expanding rapidly to address emerging countries andlower acuity settings where low-cost is of prime concern. In thesemarkets compromises may be made on modularity, connectivity and(sometimes) measurement quality.

In the lifestyle and sports arena also physiological measurements areused more and more (such as heart rate, respiration rate, SpO2).

In said new application spaces wearable (cordless) sensors,miniaturization and low-power are necessary. The basic requirementsacross all these segments are the same, namely excellent measurementquality compared with non-compromised electrical patient safety. Thelatter is strictly regulated in the IEC 60601 standard and dictates in aworst case scenario (direct connection to the heart) a 10 μA maximumleakage current, 4 kV isolation towards ground and 1.5 kV isolationbetween each of the measurements. Additionally, the patient monitor mustbe able to withstand high differential voltages introduced by adefibrillator and large RF voltages from a surgical knife.

Conventional isolation and protection concepts are based on inductivepower couplers (transformers) and optical data couplers for datatransport, next to maintaining sufficient creeping and clearance betweenPCBs and connector pins.

U.S. Pat. No. 6,819,013 B2 discloses an electrically isolated, combinedpower and signal coupler for a patient connected device. A dockingstation and a portable device, capable of docking with the dockingstation each include a power coupler and an electrically isolated datatransducer. The respective power couplers include a magneticallypermeable element including a central pole and a peripheral pole and aprinted circuit board with an opening through which the central poleprotrudes. The printed circuit board includes windings surrounding thecentral pole opening including a primary winding in the docking stationand a secondary winding in the portable device. When the portable deviceis docked with the docking station, the magnetically permeable elementin the portable device and the magnetically permeable element in thedocking station are arranged to form a magnetic circuit, and the datatransducer in the portable device and the data transducer in the dockingstation are arranged to exchange data.

US 2013/046197 A1 discloses a docking apparatus comprising a processor,a battery charging module, a storage device, and one or more ports,which are configured to couple with patient monitoring units. Eachpatient monitoring unit is operable to monitor at least onephysiological parameter of a patient. The battery charging modulecharges the patient monitoring units through the ports. The storagedevice stores data received from the patient monitoring units throughthe ports. The processor transmits updates to the patient monitoringunits through the ports. The ports may comprise sockets that receiveplugs from cables of the patient monitoring units. The docking apparatusmay comprise a plurality of separate dock housings associated withcorresponding patient monitoring units. These dock housings being joinedtogether in a daisy chain. The docking apparatus may also include aplurality of docking recesses in a single housing, with each dockingrecess being associated with a corresponding patient monitoring unit.

Mark Cantrell: “Digital Isolator Simplifies USB Isolation in Medical andIndustrial Applications”, Analog Dialogue 43-06, June (2009),XP055052417, www.analog.com/analogdialogue, discloses various ways ofapplying isolation with USB, e.g. an isolated cable interface includinga a chip-scale device that supports direct isolation of low- andfull-speed USB D+ and D− lines.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a cable unit forconnecting devices in a system to enable wireless exchange of dataand/or power between them, which can be seamlessly integrated into asystem of devices, enables easier workflows within the system in variousscenarios and settings and guarantees consistent exchange of data andpower.

In an aspect of the present invention a cable unit is presented forconnecting devices in a system, in particular in a patient monitoringsystem, to enable wireless exchange of data and/or power between them,said cable unit comprising:

a cable and

a connector arranged at each end of said cable, said connectorcomprising a data transmission unit for transmitting data to and/orreceiving data from a device having a counterpart connector and amagnetic coupling unit for transmitting power to and/or receiving powerfrom another device of the system having a counterpart connector by useof inductive coupling.

Preferred embodiments of the invention are defined in the dependentclaims.

Wireless measurements, e.g. in a clinical setting, are generally gainingimportance. However, conventional wireless data and battery poweredmonitoring devices are not reliable and safe in high acuity (OR, ICU)settings. Further, the consistency and integrity of wirelesslytransmitted data and power are important issues which shall beaddressed. Further, the capacity of the available radio spectrum islimited, especially in a crowded area like hospitals, and cable clutteris still an important drawback of wired sensors. In conclusion, there isa strong need for a reliable wired connection technique for data andpower, which is universally applicable in all patient monitoringsettings and which can generally be used for transmission of data andpower between devices of a system.

The present invention is based on the idea to provide a cable unit (alsocalled coupling cable, making use of a contactless and cordlessconnector approach for the inductive power transmission and for datatransmission, e.g. by use of RF transmission. This cable unit forms aprotected pipe for (bi-directional) data and power signals, has lowsignal attenuation for magnetic power and data, and offers shielding ofexternal and internal crosstalk and disturbances.

The benefits of the proposed cable unit are that it maintains aconnection technology that is also used by the other devices of thesystem to enable a flexible and arbitrary coupling of all devices andmodules within the system using the same data link and the samepowering. Generally, the cable unit is not radio-standard dependent. Itcan be used for BT, BT-LE, Wi-Fi, Ant etc. The bandwidth can beoptimized for any required frequency band, e.g. 430 MHz, 2.4 GHz and/or5 GHz application. A guaranteed power transfer and a high integrity datalink offer consistent measurement functionality. Further, a reducedoccupation of the RF spectrum (in case of using RF data transmission, asproposed in an embodiment) is achieved by shielding and transmit powerreduction, which is an important feature in crowded areas like hospitalsand the home. Still further, a seamless transition between wired andnon-wired applications can be made, i.e. a cable unit needs only be usedwhen really needed, and the same cable unit can be used across the wholearchitecture. No galvanic contacts are provided so that the cable unitis thus easily cleanable and easily replaceable. An extra galvanicisolation may also be provided.

The advantages of the proposed approach are that contactless powertransfer avoids the need of galvanic contacts and offers implicitgalvanic isolation. Further, an easy workflow can be installed due to acommon interfacing with other devices of the system by magneticcoupling, i.e. all devices preferably use the same (mechanical andelectrical) interface.

In an embodiment the cable unit further comprises a second connector (oreven more connectors) arranged at least at one end of said cable forsimultaneously transmitting data to and/or receiving data from twodevices and/or for simultaneously transmitting power to and/or receivingpower from two devices. This allows for connecting two or more of suchcable units and for using such cable unit to form a daisy chain or starconfiguration. Hence, simultaneous bidirectional exchange of data and/orpower is possible.

A two-way power transfer may be achieved by two full-fledged one-waymagnetic powering channels, as e.g. standardized in the Qi standard orPowerMat standard. This requires four coils (two transmit coils and tworeceive coils). In another embodiment two sets of one-way magneticpowering channels, multiplexed to two coils, may be used. Still further,one set of two-way magnetic powering channels (two transmit/receivecoils) may be used.

Active components may be present (in both connectors) to convert themagnetic (Qi) power signals to clean/stabilized DC or sinusoidal ACbefore sending them across the cable. This limits crosstalk anddisturbances from the power signal into the radio channel. The locationof said components is preferably in the connectors(s), but they can alsobe distributed across (a part of) the cable unit, e.g. on a flexiblefoil integrated in the cable sleeve.

In another embodiment the cable unit further comprises a sealed housingarranged at each end of the cable, in which the one or more connectorsarranged at the respective end of the cable are arranged. The sealedhousing (e.g. a sealed box at each end of the cable) is robust, wellprotected and fluid tight, and preferably has no edges and no grooves.The cable unit is thus easily cleanable and easily replaceable. Thesealed housing is preferably configured to allow stacking of the cableunit to other devices having a counterpart connector.

Further, easy click-on or slide-in mechanisms and/or magnetic fixationsmay be used to align and fixate the connectors in an optimal positionfor power transfer and/or to improve wireless data transmissionperformance.

The cable unit may be purely passive, i.e. it just forwards receiveddata and power by connecting coils. Alternatively, electronic circuitryfor data processing, impedance matching, conversion and/or storage ofreceived data may be provided, such as converters to enable e.g.baseband or optical data transmission, RF amplifiers and RFtransponders, which may be added to the connectors or to the cableitself.

In another embodiment the cable unit further comprises a detection unitfor detecting the strength of magnetic coupling between the magneticcoupling unit and a magnetic coupling unit of another device, and acontrol unit for switching the data transmission unit into a low-powermode and/or for enabling the magnetic coupling unit, if the detectedmagnetic coupling is above a first threshold and/or its increase isabove a second threshold, and for switching the data transmission unitinto a high-power mode and/or for disabling the magnetic coupling unit,if the detected magnetic coupling is below a third threshold and/or itsdecrease is above a fourth threshold.

This embodiment is based on the idea to make use of a connectortechnology which can operate in two modes, namely a near-field mode anda far-field mode. When a connector of the cable unit is mechanicallyconnected to a counterpart connector of another device, the near-fieldmode is used in which the radio (i.e. the data transmission unit)switches to low-power mode, the magnetic power transfer is enabled, andthe RF radiation and the magnetic fields are shielded from themeasurement electronics and the outside world. When left unconnected,the far-field mode is used in which the radio switches to high-powermode to enable short-range radio communication and the magnetic powertransfer is disabled. For controlling the switching between the twomodes the magnetic coupling and/or its increase or decrease is detectedbetween a detector and a potential counterpart connector. Predeterminedthresholds for the magnetic coupling and/or its increase/decrease arethen used to decide about the switching between the different modes.

In another embodiment the cable unit further comprises a proximitydetector for detecting proximity of the cable unit to another device anda control unit for switching the data transmission unit into a low-powermode and/or for enabling the magnetic coupling unit, if a device isdetected to be proximate to the cable unit, and for switching the datatransmission unit into a high-power mode and/or for disabling themagnetic coupling unit, if no device is detected to be proximate to thecable unit. A predetermined distance threshold may be used by theproximity detector, which distance threshold may e.g. depend on thedesign of the devices and the cable unit and the particular application.Generally, direct or indirect means for detecting proximity of the cableunit to another device may be used.

The actual distance between a cable unit and another device that can bedetected as “proximate” depends e.g. on the magnetic design; onecriterion may be if the magnetic coupling is larger than 90% orpreferably larger than 95%, or ultimately larger than 99%. In anexemplary design a magnetic distance of ˜0.5 mm+100 μm (due to 2*0.25 mmplastic housing) is used. However, other distances may be used instead,depending on the particular design and/or application.

In another embodiment said data transmission unit is configured fortransmitting data by use of RF transmission, optical transmission,capacitive coupling or near field communication.

Preferably, said connector further comprises a carrier, wherein saiddata transmission unit comprises an RF antenna arranged in or on thecarrier and an RF circuit for driving the RF antenna and/or obtaining RFsignals received by the RF antenna. Various designs of the RF antennaare generally possible. Preferred antenna designs include that the RFantenna is shaped in the form of a stripe, ring, planar inverted F orplanar folded dipole. Further, the RF antenna is preferably arrangedrotational symmetrically, which avoids the need for a predeterminedrotational positioning of the connector with respect to a counterpartconnecter when connecting them. In an exemplary implementation a quarterwavelength planar inverted F-antenna may be used.

In another embodiment said magnetic coupling unit comprises a fluxconcentrator for concentrating magnetic flux and one or more coilsarranged around part of the flux concentrator. Thus, inductive couplinglike in a transformer is preferably used for the transmission of power.

Preferably, said magnetic coupling unit comprises:

a ring-shaped flux concentrator, at least part of which having aU-shaped cross-section forming a recess between the legs of the U,

a first coil arranged within a recess of the flux concentrator, and

a second coil arranged first coil outside of the recess in which thefirst coil is arranged, wherein the sealed housing is arranged to allowstacking of the battery module upon other devices having a counterpartconnector so that the first coil of the connector and a second coil of aconnector stacked upon the connector together form a first transformerfor inductive power transmission there between and/or the second coil ofthe connector and a first coil of a third connector stacked upon theconnector together form a second transformer for inductive powertransfer there between.

This embodiment is based on the idea to provide a modular approach sothat multiple devices and cable units can be stacked on top of eachother. The flux concentrator, e.g. a core as used in a transformer, thecoils and particularly the housing are configured such that two or moreof the connectors can be easily stacked together to enable the desiredwireless coupling for performing cordless power transfer (and,optionally, also wireless data transfer) between the connectors stackedtogether.

When stacked, upper and lower (i.e. first and second) coil are bothenclosed by the same magnetic material of part of the flux concentratorsof the stacked connectors, i.e. these part of the two flux concentratorsa closed magnetic loop. This makes the two coils intimately magneticallycoupled. According to an embodiment a bulge may be formed in the housingthat fits into the recess of the stacked connector, which makes theconnectors easily stackable.

There are generally two arrangements possible for the flux concentratorand the coils of a connector. In one arrangement the coils are arrangedabove each other in a vertical direction, and in the other arrangementthe coils are arranged one with respect to the other in lateraldirection. The main advantages achieved by the common approachunderlying these two arrangements of the proposed stackable connectorare flexibility and the absence of galvanic contacts, thus providingsufficient reliability and enabling an easy cleaning, as well aselectrical isolation between devices having such connectors.

The housing may be configured as a circular-symmetrical dish-sized,plastic sealed box. Hereby, circular symmetrical geometries comprisepolygonal (triangle, square, etc.) and ultimately circular shapeddishes. The flux concentrator may be an inverted-U shaped fluxconcentrator made of high permeability material. Preferably, the fluxconcentrator has a low permeability for RF, or the walls may be claddedwith conductive material to shield and guide the RF field. Power controlmeans may be provided to exchange energy with the coils. An RF antennaand radio means may be provided for enabling cordless data transmission.

The cable preferably comprises a pair of twisted wires between themagnetic coupling units of the connectors and/or a coaxial cable orbalanced transmission line between the data transmission units of theconnectors.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention will be apparent from andelucidated with reference to the embodiment(s) described hereinafter. Inthe following drawings

FIG. 1 shows a schematic diagram of a known system including a pluralityof devices,

FIG. 2 shows a schematic diagram of a first embodiment of a systemincluding a plurality of devices according to the present invention,

FIG. 3 schematically shows a first embodiment of a connector for use inthe system according to the present invention,

FIG. 4 schematically shows a second embodiment of a connector for use inthe system according to the present invention,

FIG. 5 schematically shows a third embodiment of a connector for use inthe system according to the present invention,

FIG. 6 schematically shows a fourth embodiment of a connector for use inthe system according to the present invention,

FIG. 7 schematically shows a fifth embodiment of a connector for use inthe system according to the present invention,

FIG. 8 shows a schematic diagram of a second embodiment of a systemaccording to the present invention,

FIG. 9 shows a schematic diagram of a third embodiment of a systemaccording to the present invention,

FIGS. 10A and 10B schematically show a cross-sectional view and a topview respectively of a sixth embodiment of a connector for use in thesystem according to the present invention,

FIG. 10C schematically shows a sixth embodiment of a connector for usein the system according to the present invention in the connected state,coupled to a counterpart connector,

FIG. 11 schematically shows a seventh embodiment of a connector for usein the system according to the present invention,

FIGS. 12A and 12B schematically show a cross-sectional view and a topview respectively of an eighth embodiment of a connector for use in thesystem according to the present invention,

FIGS. 13A and 13B schematically show a cross-sectional view and a topview respectively of a ninth embodiment of a connector for use in thesystem according to the present invention,

FIGS. 14A and 14B schematically show a cross-sectional view and a topview respectively of a tenth embodiment of a connector for use in thesystem according to the present invention,

FIG. 15 schematically shows an eleventh embodiment of a connector foruse in the system according to the present invention,

FIG. 16 schematically shows the layout of a connector with automaticswitching between modes,

FIGS. 17A, 17B, 17C, and 17D schematically show a cross-sectional view,a top view, and first and second perspective views respectively of afirst embodiment of a stackable connector for use in the systemaccording to the present invention,

FIGS. 18A, 18B, and 18C schematically show a cross-sectional view, andfirst and second perspective views respectively of a stack of twoconnectors according to the first embodiment,

FIG. 19 schematically shows a stack of three connectors according to thefirst embodiment,

FIGS. 20A, 20B, and 20C schematically show arrangements of severaldevices in the form of a daisy chain, each device including one or moreof the connectors according to the invention,

FIGS. 21A and 21B schematically show a cross-sectional view and a topview respectively of a second embodiment of a stackable connector foruse in the system according to the present invention,

FIGS. 22A and 22B schematically show a cross-sectional view and a topview respectively of a third embodiment of a stackable connector for usein the system according to the present invention,

FIGS. 23A, 23B, and 23C schematically show a cross-sectional view, a topview, and a simplified cross-sectional view respectively of a fourthembodiment of a stackable connector for use in the system according tothe present invention,

FIG. 24 schematically shows a fifth embodiment of a stackable connectorfor use in the system according to the present invention,

FIGS. 25A and 25B schematically show a cross-sectional view and a topview respectively of a sixth embodiment of a stackable connector for usein the system according to the present invention,

FIGS. 26A and 26B schematically show a cross-sectional view and a topview respectively of an embodiment of a connector for use in the systemaccording to the present invention having a lateral geometry,

FIGS. 27A and 27B schematically show a cross-sectional view and a topview respectively of a daisy chain using connectors as shown in FIGS.26A and 26B,

FIGS. 28A and 28B schematically show a cross-sectional view and a topview respectively of a body worn sensor arrangement using connectors asshown in FIGS. 26A and 26B,

FIG. 29 schematically shows the coupling of different modules and unitsto a patient monitor using connectors as shown in FIGS. 26A and 26B,

FIG. 30 shows a schematic diagram of a fourth embodiment of a systemaccording to the present invention comprising a battery module,

FIG. 31 shows a general layout of a cable unit according to the presentinvention,

FIG. 32 illustrates the use of a cable unit in a high acuity setting,

FIG. 33 illustrates the use of a cable unit in a lower acuity setting,

FIG. 34 shows a schematic diagram of a fifth embodiment of a systemaccording to the present invention comprising a storage module,

FIG. 35 shows a schematic diagram of an embodiment of a battery moduleaccording to the present invention,

FIG. 36 shows a schematic diagram of an embodiment of a cable unitaccording to the present invention, and

FIG. 37 shows a schematic diagram of another embodiment of a deviceaccording to the present invention applying a paring approach.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a schematic diagram of a known system 1 including aplurality of devices 2, 3, 4, 5, which are configured to transmit powerand data between them. Conventionally, a modular approach is usedaccording to which measurement modules 3, 4 (representing one type ofdevices) are connected via expensive gold-plated mainboard connectors(i.e. via a galvanic connection) 8 to a central processing unit 2(representing another type of devices), e.g. a central processor on amainboard of a patient monitor. Further, an isolated measurement module5 on the main board (representing another type of device) may beconnected to the main processing unit 2 in the same way.

Some measurements may be implemented directly on the mainboard itselfMeasurements are e.g. isolated from each other by using optocouplers 6for data transmission and a transformer 7 for power transmission. Allmetal parts share the same (protected) earth connection; themeasurements themselves are isolated from earth. Each measurement module3, 4, 5 may be connected, generally via a cable, to one or more sensors(not shown), e.g. a pulse oximetry sensor, an accelerometer, ECGelectrodes, that are placed at the patient's body.

In such a system electrical isolation involves a large part (at least30%) of the measurement costs. Further, mainboard connectors areexpensive and mechanically complex and cleaning is a challenge. Loweringthe costs is a strong requirement in the value segment and lower acuitysettings. Modularity is a strong requirement in high-end markets, andsomewhat less in lower acuity and value segment markets. Wearable(cordless) sensors and low-power are important for lower acuity caresettings. Further, aligning measurement concepts across the productrange of a company lowers costs and maintains the same quality for allmarket segments.

Thus, there is a strong need for a low-cost, low-power, flexible andmodular architecture, which is universally applicable to all patientmonitoring settings or, more generally, to all systems comprising aplurality of (different and/or identical devices) in which power and/ordata need to be transmitted under some or all of the above constraints.

FIG. 2 shows a schematic diagram of a first embodiment of a system 10including a plurality of devices 20, 30, 40, 50 according to the presentinvention. According to the embodiment the devices 30, 40, 50 (e.g.representing measurement modules 30, 40, 50) are each connected in awireless manner to the central processing unit 20, e.g. a patientmonitor. Measurement modules, for instance in a patient monitoringsystem, are connected to the central processing unit 20 by individualmagnetically coupled power transfer and near field contactless datatransfer (whereby there may also be devices which only provide means foreither magnetically coupled power transfer or near field contactlessdata transfer). This flexible architecture complies with the followingapplications of physiological measurements: measurement modules locatedon the main board (i.e. in the central processing unit 10), modular‘plug-in’ measurement modules, measurement modules located in a mobilemeasurement server connected to the central processing unit 10, andcordless measurement modules. Generally, such measurement modules aregalvanically insulated from each other. Measurement modules may also becombined in one single mechanical enclosure, and they may be fullygalvanically insulated via their own coils.

Magnetic power coupling may e.g. be integrated in tracks of the(mainboard) PCB or implemented as magnetic coils in each of the twodistinct parts of a connector for connecting two devices.

Contactless data transfer between two devices is preferably achieved vianear-field communications means, e.g. Bluetooth 4.0 (low energy), Wi-Fi,ZigBee, capacitive (e.g. via the parasitic capacitance of the magneticcoupling) or optical, wherein radio transfer is the preferred option.Preferably a (e.g. standardized) radio protocol is used to be compliantwith all four applications mentioned, e.g. BLE, which is alreadyintegrated in many Commercial-Of-The-Shelf (COTS) components. Basically,in case the radiation field is confined within a certain volume (e.g.inside the housing of the monitor) any non-regulated radio protocol canbe used.

Generally, each device that shall be able to transmit data and power ina cordless manner comprises a housing, a magnetic coupling unit arrangedwithin the housing for transmitting power to and/or receiving power fromanother device of the system having a counterpart connector by use ofinductive coupling, and a data transmission unit arranged fortransmitting data to and/or receiving data from another device of thesystem having a counterpart connector, in particular by use of RFtransmission, optical transmission, capacitive coupling or near fieldcommunication.

The measurement modules 30, 40 each comprise a housing 31, 41, amagnetic coupling unit 32, 42 and a data transmission unit 33, 43.Further, each of them comprises a patient side connection unit (PSC) 34,44 for (generally in a galvanic manner) connecting the respectivemeasurement module 30, 40 to a sensor or electrode (not shown) in orderto receive data signals from the sensor or electrode and/or transmitcontrol signals to the sensor or electrode. Optionally, further meansfor analog processing and/or digital processing may be provided, and ameasurement module could contain a small energy buffer (e.g. a batteryor super-capacitor) to bridge the transition time between wired-wirelessscenarios as well as during battery replacement.

The isolated measurement module 50, i.e. a measurement module integratedon the main board of the patient monitoring device, comprises a housing51, a magnetic coupling unit 52 and a data transmission unit 53.Further, it comprises a patient side connection unit (PSC) 54 as well.

The central processing unit 20 comprises a housing 21, several magneticcoupling units 22, 22 a, 22 c and several data transmission units 23, 23a, 23 b, which may also be combined into a single data transmissionunit, wherein a magnetic coupling unit and a data coupling unit form aconnection module for connecting one (external) device to the centralprocessing unit 20. Further, it comprises a supply terminal 24comprising an isolation barrier for coupling the central processing unit20 to an external power supply 60. Furthermore, the central processingunit 20 generally contains all the hardware needed for power and voltagegeneration, control, input/output, display and central processing ofdata from measurements and alarm generation.

The ability to transmit data and power between two devices of the system10 is indicated through blocks 61, 62, 63. It should be noted that thesystem 10 may also comprises devices, which are not configured fortransmitting and receiving data and power, but which are configured toonly transmit data and/or power or which are configured to only receivedata and/or power.

A first embodiment of a connector 100, 110 for wireless transmission ofdata and/or power between separate devices comprising such a connectoris schematically shown in a top view in FIG. 3. These connectors 100(e.g. of a central processing unit) and 110 (e.g. of a measurementmodule) represent a low-cost solution and can be implemented on-board.The tracks of a PCB 102, 112 may be used as transformer windings (i.e.coils) 101 (e.g. representing a primary coil), 111 (e.g. representing asecondary coil), separated in the horizontal and/or the verticaldirection. Magnetic coupling may be enhanced by adding a fluxconcentrator 103, e.g. a ferromagnetic core having two legs (eachcarrying one of the coils 101, 111) and two yokes connecting the twolegs to form a ring (which need not necessarily circular, but may alsohave other shapes such as rectangular, elliptical, etc. RF antennas 104,114 are integrated on the PCBs 102, 112 as well. A gap 105 between theconnectors 100, 110 provides an isolation barrier. A mainboard processor106 may be provided in the central processing unit and a measurementunit 116 may be provided on the measurement module.

FIG. 4 schematically shows a cross-sectional view of a second embodimentof a connector 120, 130 for use in the system according to the presentinvention providing isolated measurement on the mainboard of the centralprocessing unit. The coils 101, 111 are located on different surfaces ofthe respective PCB 102, 112 and are magnetically coupled via a fluxconcentrator 103.

Obviously, many variations on this approach are feasible. FIG. 5schematically shows a cross-sectional view of a third embodiment of aconnector 140, 150 for use in the system according to the presentinvention. In this embodiment a third in-between layer 107 is provided,which is arranged within the PCB 102, in vertical direction, on a heightlevel in between the coil 101 and the coil 111. The third in-betweenlayer 107 is connected to ground to reduce stray capacitive couplingbetween the coils 101, 111. Further layers, such as another ground layer108, may be added for EMC reasons, as shown in FIG. 6 depicting a fourthembodiment of a connector 160, 170 for use in the system according tothe present invention.

FIG. 7 schematically shows a cross-sectional view of a fifth embodimentof a connector 180, 190 for use in the system according to the presentinvention. In this embodiment the measurement PCB 112 is located on topof the mainboard PCB 102 with an insulation foil 109 in between andmagnetically coupling via the flux concentrator 103.

In still another variation of one of the above described embodiments thesecondary coil may be integrated on the die or in the package of anASIC, which comprise the electronic circuitry of the measurement.

Preferably, the main microprocessor on the central processing unitcontrols or drives the primary coil of the transformer. The AC voltageof the secondary coil is rectified and stabilized to supply themeasurement module. This approach may make use of the Qi standard (orother standard) of wireless charging, and the arrangement andconstruction of the components can generally be made to fulfillrequirements of one or more of these standards (e.g. the coils should beclose to the surface).

For data communication the central processing unit may comprise a nearfield radio-stack, communicating with the isolated measurements via e.g.Bluetooth Low Energy, ZigBee or in any other suitable way. Everynon-standard protocol is allowed in case the radiation is limited to aconfined housing.

RF transmission may be achieved via separate antennas, via capacitivecoupling pads or even via the parasitic capacitance of the transformercoils. Said parasitic capacitance should be kept very small to becompliant with the IEC 60601-2-49 standard isolation requirements, butthis constraint is e.g. achievable with transmission in the UHF radioband of 2.4 GHz or beyond.

FIG. 8 shows a schematic diagram of a second embodiment of a system 11including a plurality of devices 20, 30, 40 according to the presentinvention. In this embodiment the one or more measurement modules 30, 40are e.g. fitted in a measurement rack 20′and are coupled to the centralprocessing unit 20 by magnetic connectors 25, 35 (for the module 30) and26, 46 (for the module 40) comprising a primary coil 101 of the centralprocessing unit 20 in close proximity to a secondary coil 111 and RFantenna 114 of the modules 30, 40. For data transmission an RF antenna104 may be provided in the central processing unit 20 and acorresponding RF antenna 114 may be provided in the measurement modules30, 50 (e.g. an antenna used in near-field mode for bridging smalldistances, such as BT, ZigBee, etc.

Due to the absence of pins, cleaning is easy. Hence, these connectors25, 35, 26, 46 replace the expensive and cumbersome cleanable galvanicconnectors as conventionally used and as shown in FIG. 1. Further, PSCunits 34, 44 may be provided for connection to respective sensors, e.g.a temperature sensor or a SpO2 sensor.

The system may further comprise a user interface 70 coupled to thecentral processing unit 20, e.g. comprising one or more displays,buttons, switches, etc. Further, a mains power transformer 71 may beprovided for connection to a mains power supply 60.

Measurements may be located inside a detachable small box (not shown),also called measurement server, close to the patient, which is connectedto the patient monitor via a cable comprising connectors as disclosedherein or via a wireless link, so that it can be operated in a hybridmode (i.e. in wired or wireless way). Within such a measurement serverevery measurement's battery will be charged during normal use. Whenevera patient needs to be moved, the link to the patient monitor might belost for a certain amount of time; nevertheless the individualmeasurements will continue to measure, record and process all the vitalsigns. Hence, no important data regarding the patient's health status islost. Again, in the vicinity of a patient monitor, the data might besynchronized again with a central server.

By putting in an additional re-chargeable battery 37, 47 into themeasurement modules 30, 40, as shown in FIG. 9 showing anotherembodiment of a system 12 according to the present invention, theautonomous operation of said measurement modules is possible. Whenre-fitted into the measurement rack the battery is charged via themagnetic coupling. Battery management is at the measurement module andmay (optionally, but not preferably) be made according to the Qistandard for wireless charging.

Data transfer preferably complies with existing connectivity standards.For example when using the Bluetooth LE 4.0 radio, the patient monitorbecomes direct applicable for the Continua Health Alliance, which is anon-profit open industry organization of healthcare and technologycompanies joining together in collaboration to improve the quality ofpersonal healthcare. The Continua Health Alliance is dedicated toestablishing a system of interoperable personal connected healthsolutions with the knowledge that extending those solutions into thehome fosters independence empowers individuals and provides theopportunity for truly personalized health and wellness management. Theseaims are supported by the present invention.

FIGS. 10 to 15 show further embodiments of a connector according to thepresent invention.

FIGS. 10A and 10B schematically show a cross-sectional view (FIG. 10A)and a top view (FIG. 10B) of a sixth embodiment of a connector 200 foruse in the system according to the present invention in an unconnectedstate. The connector 200 comprises a PCB 202, which comprises a quarterwavelength planar inverted F-antenna (PIFA) 204 as part of the datatransmission unit integrated in the tracks 290. The RF antenna 204 isformed by an RF signal line 205 and a ground plane 206. The magneticfield is generated by coils 201 a, 201 b wrapped around the C-shaped(also called U-shaped) flux concentrator 203 made from a material withhigh magnetic permeability for the frequencies of interest. Additionalconducting sheet material may be added (as cover) to short the remainingstray field in the electronics by eddy currents. Additional cladding ofthe core 203 may help to shield the RF signal, which is a short-rangeradio field 209. When no other connector is attached (i.e. in theunconnected state), the RF antenna 204 operates in the far-field mode,wherein its directivity is pointed to the outside world as indicated inFIG. 10A.

A power unit 207 is coupled to the coils 201 for power supply to thecoils 201 and/or power reception from the coils 201. An RF unit 208 iscoupled to the RF antenna 204 for data supply to the RF antenna 204and/or data reception from the RF antenna 204.

In the connected state, as illustrated in FIG. 10C showing the connector200 coupled to a counterpart connector 210, the poles of both C-shapedflux concentrators 203, 213 and the antennas 204, 214 are almostperfectly aligned, so that the RF and magnetic fields are optimallycoupled and shielded from the outside world.

Connecting induces two effects:

i) Firstly, the magnetic coupling increases dramatically, e.g. fromk=0.5 to k>0.95, which may be detected directly (e.g. via the inducedvoltage) or indirectly (e.g. using proximity detection). Via a pollingmechanism this effect is recognized by the magnetic powering electronics(e.g. Qi, PowerMat or custom) via the changed coil impedance, resonancefrequency or induced voltage. In the unconnected state the magneticpowering is disabled, hence no interference is induced into the radiochannel or in the measurement. In the connected state, the flux is verywell confined into the flux concentrators 203, 213, which also preventinterference. Disconnecting may be detected by polling the oppositeeffect (by briefly switching off the coil and observing the resultingeffect).

ii) Secondly, due to the very short distance between the two antennas204, 214, the amplitude and SNR of the received RF signals increasessignificantly. The radio transmitters can now scot-free switch to anear-field mode by lowering their output power while maintainingconsistent data communication. Consequently, the radiated RF power inthe neighborhood is significantly reduced, which helps to freeing-up theradio spectrum. Furthermore, due to the efficient RF coupling, the powerconsumption of the radio is reduced.

It should be noted that RF coupling in the near-field mode, in which thedistance is a fraction of the wavelength, is more due to capacitivecoupling than far field EM waves. Both effects are validated on aregularly basis via a polling mechanism, or triggered by additionalproximity detection (optical, magnetic) or by a simple mechanical switchor a reed-switch.

To avoid stray flux a coil is preferably not powered fully(continuously) without counter-core present. However a polling mechanismmay generate power for a short time (e.g. 10 ms) every second to measuremagnetic coupling.

RF communication and/or data transfer via the magnetic coupling (as e.g.implemented in the Qi standard) or optical coupling is used to updateand negotiate IDs, required power, signal quality, charging status etc.before deciding to start nominal power transfer.

Below it will be described in more detail how the actualconnection/disconnection process triggers association in a patientnetwork and how safety is implemented.

Galvanic isolation is guaranteed by the PCB layer material and theC-core. Alternatively, extra isolation layers on top on the PCB 202, 212and the pole-tips of the C-core 203, 213 can be added. The unoccupiedarea of the PCB may be used for the measurement electronic and the PSC.Ferrite cores can be good conductors, but there are also highlyresistive (composite) ferrites available.

Alternative antenna configurations are possible, e.g. a ring shapedantenna 224 as shown in FIG. 11 depicting a top view of a seventhembodiment of a connector 220 for use in the system according to thepresent invention.

In the embodiments shown in FIGS. 10 and 11 the mechanical alignment ofthe connectors 200, 210, 220 is limited to two rotational orientationsin which the antennas and C-cores are aligned. This is a seriousdrawback when using cables in body-worn measurements and daisy chainconfigurations. This problem is solved by a rotational symmetricalconnector 230 as shown in FIGS. 12A and 12B showing a cross-sectionalview (FIG. 12A) and a top view (FIG. 12B) of an eighth embodiment of aconnector 230 for use in the system according to the present invention.

The inner leg 232 of the E-core 231 (i.e. a core having a cross-sectionforming an E) carries the coil windings 201 for magnetic powering. TheRF antenna 204 is arranged in the PCB 201 between the inner leg 232 andthe outer legs 233 (which is actually a single ring as shown in FIG.12B). The legs 232, 233 are connected by a yoke 236. The inner or outerwalls of the core 231 may also be cladded with conductive material tofurther reduce interference. When two of such connectors are connected,the two halves form a pot-core where the magnetic field and the radiosignals are thus very well coupled and shielded. In addition, ameasurement unit 234 and a PCS unit 235 may be provided.

Alternatively, the RF antenna 204 is located outside the magnetic core231, i.e. around the outer legs 233, which may contribute to even lesscrosstalk and interference between the RF and magnetic signals. This isillustrated in FIGS. 13A and 13B showing a ninth embodiment of aconnector 240 for use in the system according to the present invention.

FIGS. 14A and 14B show a cross-sectional view (FIG. 14A) and a top view(FIG. 14B) of a tenth embodiment of a connector 250 for use in thesystem according to the present invention comprising a rotationalsymmetrical C-core 251 forming a ring having a C-shaped cross-sectionformed by two legs 252, 253 connected by a yoke 254. The magnetic fluxgenerated by the coil 201 is indicated by arrows 255. The RF antenna 204is arranged between the inner legs 252 of the C-core 251.

FIG. 15 shows a cross-sectional view of an eleventh embodiment of aconnector 260 for use in the system according to the present invention,which is similar to the tenth embodiment shown in FIG. 14, but in whichthe RF antenna 204 is arranged around the outer legs 252 of the C-core251.

The connectors shown in FIGS. 10 to 15 provide the advantage that theyare rotational symmetrical and that—in connected state—there is a verysmall gap between the connector and its counterpart connector.

FIG. 16 schematically depicts the layout of a connector 270 (such as theconnectors shown in FIGS. 10 to 15) for wireless transmission of dataand/or power between separate devices comprising such a connector. Theconnector 270 comprises a data transmission unit 271 (e.g. comprising anRF antenna 204) arranged for transmitting data to and/or receiving datafrom another device of the system having a counterpart connector,preferably by use of RF transmission. The connector further comprises amagnetic coupling unit 272 (e.g. comprising a coil 201 and a core 203)for transmitting power to and/or receiving power from another device ofthe system having a counterpart connector by use of inductive coupling.A detection unit 273 (e.g. comprising a power unit 207) is provided fordetecting the strength of magnetic coupling between the magneticcoupling unit 272 and a magnetic coupling unit of the counterpartconnector. A control unit 274 switches the data transmission unit 201into a low-power mode and/or enables the magnetic coupling unit 272, ifthe detected magnetic coupling is above a first threshold and/or itsincrease is above a second threshold. Further, the control unit 274switches the data transmission unit 271 into a high-power mode and/ordisables the magnetic coupling unit 272, if the detected magneticcoupling is below a third threshold and/or its decrease is above afourth threshold. The thresholds may be predetermined, e.g. derived froma simulation or from measurements. This embodiment enables the automaticsetting of the correct mode of the connector which particularlyminimizes power consumption, crosstalk and usage of RF bandwidth.

It should be noted that the detection unit 273 and the control unit 274disclosed in FIG. 16 may generally be used in all other connectorsdisclosed herein.

FIGS. 17 to 28 show a plurality of embodiments of a stackable connectoraccording to the present invention for explaining details of such astackable connector.

FIGS. 17A, 17B, 17C, and 17D schematically show a first embodiment of asingle stackable connector 300 for use in the system according to thepresent invention, wherein FIG. 17A shows a cross-sectional view, FIG.17B shows a top view, FIG. 17C shows a first perspective view and FIG.17D shows a second perspective view. FIGS. 18A, 18B, and 18Cschematically show two stackable connectors 300, 300 a of the kind asshown in FIGS. 17A-17D stacked upon each other, wherein FIG. 18A shows across-sectional view, FIG. 18B shows a first perspective view and FIG.18C shows a second perspective view. The connector 300 comprises ahousing 301 and a magnetic coupling unit 302 arranged within the housing301 for transmitting power to and/or receiving power from another deviceof the system having a counterpart connector by use of inductivecoupling. Said magnetic coupling unit 302 includes a flux concentrator303 (preferably being rotational symmetrical, e.g. ring-shaped, and madeof high-permeable material), at least part of which having a U-shaped(or C-shaped) cross-section forming a recess 304 between the legs of theU. A first coil 305 is arranged within a recess 304 of the fluxconcentrator 303. A second coil 306 is arranged opposite the first coil305 and outside of the recess 304 in which the first coil 305 isarranged. The flux concentrator 303 may one of different possible forms,such as a ring-shaped form, a circular symmetrical form, the form of asquare, triangle, rectangle, etc.

Further, a ring-shaped RF antenna 307 (as part of a data transmissionunit) arranged inside of the flux concentrator, an RF unit 308(comprising radio electronics), a power unit 309 (such as magnetic powerelectronics) and a measurement unit 310 may be provided in or on the PCB312. In the second connector 300 a a battery 311 is provided instead ofthe measurement unit 310. Further, a PSC unit 313 may be provided in theconnector, as shown in FIG. 18C, for coupling with a sensor. The outersurface of the housing is preferably fully covered by isolated material(e.g. a plastic material) for galvanic isolation, watertight sealing andmechanical stability.

The housing 301 is arranged to allow stacking of two or more of suchconnectors 300, 300 a upon each other as e.g. shown in FIGS. 18A-18C sothat the second coil 306 of the connector 300 and the first coil 305 aof the second connector 300 a (or vice versa, depending on the sequencein which the connectors 300, 300 a are stacked upon each other) stackedupon the connector 300 together form a first transformer for inductivepower transmission there between.

A circular bulge 314, 314 a formed on the top surface of the connectorsfits into the circular recess 304, 304 a on the bottom of the nextconnector. The upper coil 306 of the connector 300 together with thelower coil 305 a of the connector 300 a is thus enclosed byhigh-permeable magnetic material of the flux concentrators 303, 303 a.As a result said coils are now intimately coupled, which enablesefficient power transfer. The arrows 315 show the magnetic flux lineswhen said coils are actuated as indicated. In this way stray flux isminimized which avoids crosstalk to/from the measurements and the radiosignals. If needed conductive sheet material can be added toshort-circuit any remaining flux components.

All the components of the connector 300, 300 a including measurementunit, battery, cable connector (PSC unit) are preferably fitted intocircular shaped sealed box 301, 301 a representing the housing. Due tothe rotational symmetric design, no particular positioning of twoconnectors in radial direction is required for stacking, but in this wayconnectors can be easily stacked on top of each other. Beside thecircular shape other shapes are possible, e.g. with reduced rotationalangle, square shape, shapes with extension in four directions, etc.

Preferably, the pole-tips of the inverted U core are not covered with(thick) plastic, because this will negatively affect the efficiency andintroduce stray flux. Isolation can be guaranteed by reducing theplastic thickness, e.g. to a few tenth of a mm. Alternatively, galvanicisolation can be guaranteed though, because (composite) ferrite materialmay have a high intrinsic resistivity and internally the coils and themagnetic core can be isolated.

The transfer of magnetic power does preferably not start before a largecoupling between coils and RF is detected, as explained above withrespect to FIGS. 10 to 16. In the example shown in FIGS. 18A-18C onlythe lower coil 305 a and the upper coil 306 are used, the other coilsare not actuated at all.

For reasons of efficient power transfer and high radio SNR, the couplingareas should be large enough. Therefore, preferably, coils 305, 306, 305a, 305 b and RF antennas 307, 307 a are located on the outer area of therespective connector 300, 300 a.

The PSC unit 313 for connecting one or more sensors to the connector 300comprising a measurement unit 310 is preferably located on the side ofthe connector 300 in order to have full freedom of stacking. But the PSCunit 313 may also be located e.g. on the upper part of the connector 300when restricted to have always a connector 300 including a measurementunit 310 on top of the stack.

FIG. 19 shows three connectors 300, 300 a, 300 b stacked upon eachother, wherein the connectors 300, 300 b are identical and configured asshown in FIGS. 17A-17D and each comprise a measurement unit 310, 310 a,whereas the connector 300 a is configured as shown in FIGS. 18A-18C andcomprises a battery 311. The measurement units 310, 310 b are thus fedby the same battery 311 of the connector 300 a (hereby, the battery 311may also be located at a different position, e.g. at the bottom or topposition). In this case, both coils 305 a, 306 a of the connector 300 aare used to supply energy to the measurement units 310, 310 b. Manyvariations on this scheme are possible, e.g. receiving power from oneconnector via one coil and at the same time supplying power to anotherconnector via another coil.

The present invention is applicable for virtual any combination ofstacked connectors including in any kind of device used in a system ase.g. shown in FIG. 2, e.g. in a patient monitoring system. Hence, one ormore measurement modules, battery units, cable units and processingunits may be easily coupled for cordless transfer of power and/or data.It enables even chaining devices to each other. A daisy chain is e.g.valuable in body worn sensing to avoid cable cluttering by connectingdevices (e.g. measurement module) via one single connection or cable(comprising connectors according to the present invention) to a patientmonitor, a powering device or a hub. This concept is illustrated inFIGS. 20A, 20B, and 20C showing the arrangement of several devices inthe form of a daisy chain, each device including one or more of theconnectors according to the invention.

FIG. 20A shows a serial coupling of three measurement modules 30, 40, 80(e.g. of the kind as shown in FIG. 2) coupled in series and coupled to acentral processing unit 20 (e.g. of the kind as shown in FIG. 2). FIG.20B shows a cross-sectional view of a stack 320 of three connectors 381,352, 361 of the kind as shown in FIGS. 17A-17D, wherein connector 381 ispart of measurement module 80, connector 351 is part of a first cableunit 350 and connector 361 is part of a second cable unit 360. The firstcable unit 350 comprises, at each of its ends, a connector 351, 352 andconnects the measurement module 80 with the measurement module 40 havinga connector 341 of the same kind. The second cable unit 360 comprises,at each of its ends, a connector 361, 362 and connects the measurementmodule 80 with the central processing unit 20 having a connector 321 ofthe same kind. A third cable unit 370 comprises, at each of its ends, aconnector 371, 372 and connects the measurement module 40 with themeasurement module 30 having a connector 331 of the same kind.

Hence, in this example, the measurement module 80 is connected to twocable units 350, 360. The cable unit 360 thus can transport power anddata for the complex of the three measurement modules 30, 40, 80 toand/or from the central processing unit 20. Data and power may berelayed, transferred and/or exchanged between the stacked connectors.Power transfer may be performed by using additional rectifier andtransmit electronics (e.g. DC/AC conversion), or by simply sharing ACcurrent between coils, which is the most efficient option in terms ofhardware.

It should be noted that the arrangement of the other stacks ofconnectors shown in FIG. 20A, e.g. of connectors 321 and 362 or ofconnectors 341, 351 and 372, is similar or identical as the arrangementof the stack 320 shown in FIG. 20B.

According to the same principle a star configuration is possible asshown in FIG. 20C instead of the series configuration shown in FIG. 20A.

It should be noted that combined power and data transport via the samecable is preferred, but alternatively any combination of short rangeradio cable and local batteries is also feasible.

FIGS. 21 to 23 show further embodiments of a stackable connector havingan alternative connector geometry compared to the connector geometryshown in FIGS. 17A-17D. FIG. 21A shows a cross-sectional view of acircular connector 390, in which the area outside the flux generator 303is occupied by measurement electronics 310 and/or a battery. FIG. 21Bshows a top view of said connector 390. FIG. 22A shows a cross-sectionalview and FIG. 22B shows a top view of a rectangular connector 391. FIGS.23A, 23B, and 23C show a smartcard sized connector 392 in across-sectional view (FIG. 23A), a top view (FIG. 23B) and a simplifiedcross-sectional view (FIG. 23C), which can be sandwiched between thewalls of a patient monitor slot 27. Via coupling units 321, 393 thecentral processing unit 20 and the connector 392 are coupled.

In an embodiment the upper and/or lower surfaces of the connectoraccording to the present invention is totally flat. This makes e.g.cleaning easier. Corresponding embodiments of a connector 400, 410 areshown in FIGS. 24 and 25. There are further embodiments possible withother alignment structures or features to ensure exact positioning andtight alignment (preferably <1 mm) between the flux concentrators ofdifferent connectors when stacked together. For instance, the gap(having a low μ) between flux concentrators (having a high μ; includingplastic insulation of housing) should be <0.5 mm+/−0.1 mm in aparticular application. Lateral displacement should be small compared togeometry of poles (e.g. <0.5 mm).

FIG. 24 shows a cross-sectional view of a connector 400 (including ameasurement module 310), 400 a (including a battery 311) having ahousing 407, 407 a with flat main surfaces 408, 409, 408 a, 409 a usinga flux concentrator 401, 401 a having a cross section in the form of anH. Each flux concentrator 401, 401 a comprises a first (lower) recess402, 402 a, in which the first (lower) coils 305, 305 a are arranged,and a second (upper) recess 403, 403 a, in which the second (upper)coils 306, 306 a are arranged The lower coil 305 a of the connector 400a and the upper coil 306 of the connector 300 together the lower part ofthe flux concentrator 401 a and the upper part of the flux concentrator401 form a transformer, as indicated by the arrows 404.

FIG. 25A shows a cross-sectional view of a connector 410 (including ameasurement unit 310) having flat surfaces. A top view of the connectoris shown in FIG. 25B. The connector 410 comprises two flux concentrators411, 421, each having a U-shaped cross-section and each forming a recess412 and 422, wherein each recess is formed between two neighboring legs414, 415 and 424, 425 of the respective U, i.e. between the respectiveouter ring 414, 424 and the respective inner ring 415, 425 (which is acentral finger in this embodiment). A first coil 417 is arranged withinthe recess 412 of the first flux concentrator 411 and a second coil 427is arranged within the recess 422 of the second flux concentrator 421.

The two flux concentrators 411, 421 may also be seen as a commonH-shaped flux concentrator, in which the two legs 414, 415, 424, 425 ofthe H-shaped flux concentrator 421 are arranged adjacent to each otheror formed integrally and in which the transverse joint between the legsof the H is split into two joint elements 419, 429 with a shielding 418arranged there between and perpendicular to the legs 414, 415, 424, 425of the H.

The concept of stacking can also be converted to a lateral geometry.This is beneficial to reduce building height. A cross-sectional view ofan embodiment of a connector 430 having a lateral geometry is shown inFIG. 26A and a top view of the connector 430 is shown in FIG. 26B. Theconnector 430 comprises, separately at its left side and at its rightside, coils 431, 441 arranged in the recess 437, 447 of a respectiveflux concentrator 432, 442 (each having an U-shaped cross-section likethe flux concentrators 411, 421 shown in FIG. 25A). Around the fluxconcentrators 432, 442 ring-shaped RF antennas 433, 443 are arranged.Further, two power units 434, 444, two RF units 435, 445 two PSC units436, 446 and a measurement unit 310 are provided. The flux concentrators432, 442 are thus arranged laterally displaced with respect to eachother, so that the first flux concentrator 432 and the second fluxconcentrator 442 are arranged at opposite areas and adjacent to the samesurface of the housing. The housing 439 is preferably flat or has flatsurfaces.

FIGS. 27A and 27B show a daisy chain 440 formed between measurementmodules 30, 40, each comprising a connector 430 a, 430 b as shown inFIGS. 26A and 26B, by use of a cable unit 450 comprising connectors 430c, 430 d as shown in FIGS. 26A and 26B. FIG. 27A shows a cross-sectionalview of the daisy chain, FIG. 27B shows a top view. Such a cable unit450 may comprise two or more of such connectors, preferably one at eachend, but optionally additional connectors in between the ends.

FIGS. 28A and 28B schematically show a body worn sensor arrangement 460in a cross-sectional view (FIG. 28A) and a top view (FIG. 28B). The bodyworn sensor arrangement 460 comprises a stackable support layer 461carrying a cable unit 451, similar or identical to the cable unit 450shown in FIGS. 27A and 27B, comprising connectors 452, 453, like theconnectors 430 c, 430 d or with just a single coupling unit as shown inFIG. 28A. On said cable unit one or more measurement modules 30 and/or abattery module 90 (comprising a battery), each comprising a connector430 a, 430 b, may be arranged.

Measurement modules 30, 40, 80, battery modules 90 and cable units 450can also be connected to e.g. a patient monitor or a central processingunit 20 using the same lateral geometry concept as schematically shownin FIG. 29. Further, any combination of vertical stacking and lateralconnection is generally possible with the connectors as proposed by thepresent invention. For instance, a measurement module may have bothvertical stacking and lateral stacking means.

In the following a battery module comprising a connector according tothe present invention will be described in more detail.

As described above, plug-in measurement modules are coupled to thecentral processing unit via the proposed connector using magneticpowering and RF data communication. In addition, via its RF channel abattery (or any other energy storage element) may be made part of thenetwork, e.g. a patient network, and may be coupled to other devices,such as measurement modules and the central processing unit in the samemanner. This is schematically illustrated in FIG. 30 showing a schematicdiagram of another embodiment of a system 13 including a measurementmodule 30, a central processing unit 20 and a battery module 90according to the present invention.

In a wireless measurement scenario the bi-directional battery module 90may be snapped onto the measurement module 30 to supply energymagnetically via the proposed connector. Optionally, the measurementmodule 30 itself may comprise a small buffer battery 37 (or any otherenergy storage element) for temporarily bridging the transition timebetween wired and wireless scenarios.

The battery module 90 preferably comprises a battery 91 (also calledbattery unit) and a coupling unit 92 for magnetic power transmissionbetween the battery module and other devices, e.g. to load the batterywhen the battery module 90 is coupled to the central processing unit 20and to load the battery 37 of the measurement module 30 when the batterymodule is coupled to the measurement module 30. Optionally, means fordata transmission may be provided in the battery module 90 as well.

A more detailed schematic diagram of a battery module 90′ for wirelessexchange of data and power between the battery module and another deviceof a system, in particular of a patient monitoring system, to which saidbattery module is coupled, is shown in FIG. 35. Said battery module 90′comprises a sealed housing 93, a battery unit 91 for storing electricalenergy, a data storage unit 94 for storing data, and a connector 95. Theconnector comprises a data transmission unit 96 for transmitting data toand/or receiving data from another device of the system having acounterpart connector and a magnetic coupling unit 92 for transmittingpower to and/or receiving power from another device of the system havinga counterpart connector by use of inductive coupling.

Optionally, a second connector 97 is provided for simultaneouslytransmitting data to and/or receiving data from two other devices of thesystem and/or for simultaneously transmitting power to and/or receivingpower from two other devices of the system.

The connector and its elements may be configured as explained above withrespect to other devices and other embodiments. This holds particularlyfor the magnetic coupling unit 92 and for the data transmission unit 96,which may be configured as disclosed herein, e.g. as shown in any one ofFIGS. 10 to 15 or 17 to 28.

The battery 91 may e.g. be a rechargeable battery, disposable battery ora super-capacitor and may be fitted into a smooth sealed plastic box,well protected for mechanical damage and fluids. It can be physicallyattached (i.e. put in close contact) to another device having a proposedconnector (e.g. measurement module, cable unit or patient monitor), e.g.via an easy to use snap on or slide-In mechanism. Permanent magnets oralignment structures may be used to align and fixate its position foroptimal power and radio transfer. When the battery 91 is empty, thebattery module 90 can be attached (optionally via the cable) to anydevice in the system having a compatible connector and being able tocharge, e.g. the patient monitor, a hub or a dedicated battery charger.Preferably, the same inductive/data connector topology is usedthroughout the whole architecture to couple all elements with eachother. This enables that batteries can be charged anywhere providing ahuge improvement on battery management.

Rechargeable battery life is almost always defined as number of fullcharge-discharge cycles by manufacturers and testers. In addition tocycling, the rate of degradation of lithium-ion batteries is stronglytemperature-dependent; they degrade much faster if stored or used athigher temperatures e.g. when applied to the human body.

Therefore, the health and charge condition of the battery may beconstantly determined from a temperature sensor, absolute time and thecharge- and discharge profiles by using the voltage and/or currentsensor(s), generally represented by sensor unit 98 in FIG. 35. On thebasis of this information and historical data a self-diagnosis may beperformed, which is communicated in the patient network to indicate theneed for re-charging, for replacement or any faulty condition.Historical data may be stored locally (e.g. in the battery module) aswell as shared in the network. Many scenarios are possible for thispurpose.

The battery module 90′ may further comprise a processing unit 99 fordata processing of received data, time keeping, self-diagnosis andsafety. Said processing unit may further be configured to calculate anexpected operation time when applied to a measurement module 30.

Still further, the battery module 90′ may, as illustrated in FIG. 16,comprise a detection unit 273 for detecting the strength of magneticcoupling between the magnetic coupling unit and a magnetic coupling unitof another device, and a control unit 274 for switching the datatransmission unit into a low-power mode and/or for enabling the magneticcoupling unit, if the detected magnetic coupling is above a firstthreshold and/or its increase is above a second threshold, and forswitching the data transmission unit into a high-power mode and/or fordisabling the magnetic coupling unit, if the detected magnetic couplingis below a third threshold and/or its decrease is above a fourththreshold.

The main standards in wireless power transfer are the Qi standard andthe Power Matters Technology (PowerMat) standard. Their main applicationis in the field of wireless charging. Qi comprises also a basiclocalization and recognizing mechanism for devices, low-power standbymode and power control.

An additional on-off switch using reed-contacts and a permanent magnet(e.g. the one present as part of the click-on fixation mechanism) may beuseful as an extra layer of safety and battery leakage prevention, butthere may also be other means for stacking detection, e.g. optical,capacitive or ultrasound means.

Li-ion and Li-polymer batteries are favorite candidates because of theirhigh energy density per unit of mass and its large scale of use in theconsumer domain. They have electronics means in place to watch itscharge condition and protect from over-heating. Also the Qi standard hasalready some basic means in place to recognize valid loads. These may beused according to the present invention. These basic protection andmonitoring means may according to the present invention be integratedinto the complete architecture by combining magnetic and RF coupling ascommunication means, local intelligent safety monitoring and byconnection to a patient network. For example, the absence of a valididentifier and/or the presence of a local failure condition may be areason to abandon or not to start magnetic power transfer.

The charge status may be used to determine how long a battery can beapplied for a particular measurement. This can be shown on e.g. thepatient monitor display. Optionally, when attached to a measurementmodule, a visual or audio indicator on the battery itself may indicatewhen e.g. the available measurement time is less than 1 hour beforereplacement or charging should take place.

Integrating batteries in a medical setting as described above hasserious consequences on safety, use case and workflow. Constraintsinclude absolute safety, possible shape, less weight and size, easyreplaceability/swappability by the nurse, easy cleanability, largecapacity, and chargeability during wearing. Battery modules may beclosed boxes, fully wirelessly connected for both charging as forsupplying energy. The proposed architecture offers easily cleanablemechanical connections. Furthermore, they can be replaced within a fewseconds while the measurement device stays in place.

In the following a cable unit comprising connector according to thepresent invention for connecting other devices of a network/system willbe described in more detail.

A general layout of a cable unit 500 is shown in FIG. 31. The cable unit500 comprises a cable 510 and a connector 520, 530 at each end of thecable 510. Each connector 520, 530 comprises a magnetic coupling unit521, 531 and a data transmission unit 522, 532. The cable 510 comprisesa first wire pair 511 (e.g. twisted wires) connecting the magneticcoupling units 521, 531 and a second wire pair 512 (e.g. twisted wires)connecting the data transmission units 522, 532.

FIG. 32 illustrates the use of a cable unit 500 in a high acuitysetting, in this example for connecting a measurement module 30 and acentral processing unit 20. Such a cable unit 500 may be used in an OR(operation room) or ICU (intensive care unit) setting to guarantee dataintegrity and power consistency for the measurement. The two wire pairs511, 512 are preferably thin and flexible as used in cathetertechnology. Extra conductive shielding or ferrite common mode coils maybe added for extra robustness and performance. This approach guaranteesa sufficient high signal to noise ratio for the radio signal due to itslow RF attenuation and shielding properties. Due to the large ratiobetween the frequencies for contactless powering (100˜200 kHz) and theradio (2.4 GHz) the internal crosstalk is manageable.

Many options are possible for implementing the main functionality ofthis cable unit 500 to form a protected pipe for the radio- andpower-signals.

One option is a fully passive cable unit comprising two wire pairs (asshown in FIGS. 31, 32). Basically RF data and power can be transferredin two directions across the cable unit. Twisted wires for power and acoaxial- or balanced transmission line for RF data may be used.Additionally, passive components may be added to the connector tofurther improve RF transmission by e.g. filtering and impedancematching, to improve (power) transfer by e.g. flux concentrators or forpassive identification (optical tag).

Optionally, power and radio signals may be combined in one single wirepair (or coax cable). Attaching only one connector of the fully passivecable to e.g. a measurement module will neither increase the magneticcoupling nor the RF coupling. Two connections are made until pairing isinitiated.

Another option is an active cable. Active components are present (in oneor both connectors) to convert the magnetic power signals toclean/stabilized DC or sinusoidal AC before sending them across thecable. This limits crosstalk and disturbances from the power signal intothe radio channel. The most logical location of said components is inthe connectors(s), but they can also be distributed across (a part of)the cable unit, e.g. on a flexible foil integrated in the cable sleeve.

The data radio signal may be amplified, re-modulated (transponder),buffered or (actively) impedance converted to match the RF cableproperties. Alternatively, conversion to another frequency band or tobaseband may enhance signal integrity even more, for example byconversion to a serial bus format like e.g. USB, RS232 or TCP/IP. A partof the magnetic power is used to power said active components.

Each connector may be arranged and act in itself as a node and be a partof the patient network, including unique identifier, radio and networkstack for pairing as well as magnetic powering. Additional radios may beadded to relay radio signals (e.g. in a daisy chain) or to implementseparate channels for patient network management. Active cables maytransport data or power in only one direction; hence, more wire pairsper cable or more cables may be needed to transport in both directions.

According to another option conversion of the RF signal to the opticaldomain may be provided, which offers the ultimate level in dataintegrity and potentially also allows for a thinner cable.

Obviously, cables units may comprise solely power or data channels.

Identification tags (RFID) or a radio unit may be added to the cableunit or the connectors for identification and data management.

Preferably, from a user perspective, the cable unit should be able totransport RF data and power in two directions. This may need to use morewire pairs, e.g. in case when active components are applied.

FIG. 33 illustrates the use of a cable unit 500 in a lower acuitysetting, in this example for connecting a measurement module 30 (orbattery module 90) and a central processing unit 20 only when needed forimproving RF performance (e.g. in crowded areas), or for powering orcharging reasons (i.e. saving battery capacity for mobile use).Measurement modules may be connected in a chain to avoid cablecluttering.

A more detailed schematic diagram of a cable unit 500′ for connectingdevices in a system, in particular in a patient monitoring system, toenable wireless exchange of data and/or power between them, isschematically shown in FIG. 36. As explained above, the cable unit 500′comprises a cable 510 and a connector 520, 530 arranged at each end ofsaid cable. Each of said connectors comprises a data transmission unit522, 532 for transmitting data to and/or receiving data from a devicehaving a counterpart connector and a magnetic coupling unit 521, 531 fortransmitting power to and/or receiving power from another device of thesystem having a counterpart connector by use of inductive coupling.

The cable unit 500′ further comprises a (sealed) housing 523, 533arranged at each end of the cable 510, in which the one or moreconnectors 520, 530 arranged at the respective end of the cable arearranged. The sealed housing is preferably configured as disclosedherein in the context of other devices to allow stacking of the cableunit 500′ to other devices having a counterpart connector.

The connector and its elements may be configured as explained above withrespect to other devices and other embodiments. This holds particularlyfor the magnetic coupling units 521, 531 and for the data transmissionunits 522, 532, which may be configured as disclosed herein, e.g. asshown in any one of FIGS. 10 to 15 or 17 to 28.

The cable unit 500′ may further comprise electronic circuitry 501 fordata processing, conversion and/or storage of received data.

Further, the cable unit 500′, in particular each connector 520, 530,may, as illustrated in FIG. 16, comprise a detection unit 524, 534 fordetecting the strength of magnetic coupling between the magneticcoupling unit (of the respective connector) and a magnetic coupling unitof another device, and a control unit 525, 535 for switching the datatransmission unit (of the respective connector) into a low-power modeand/or for enabling the magnetic coupling unit (of the respectiveconnector), if the detected magnetic coupling is above a first thresholdand/or its increase is above a second threshold, and for switching thedata transmission unit (of the respective connector) into a high-powermode and/or for disabling the magnetic coupling unit (of the respectiveconnector), if the detected magnetic coupling is below a third thresholdand/or its decrease is above a fourth threshold.

As an alternative option, the cable unit 500′, in particular eachconnector 520, 530, may comprise a proximity detector 526, 536 fordetecting proximity of the cable unit of another device (i.e. fordetecting if there is only a small air gap in between) and a controlunit 527, 537 for switching the respective data transmission unit 522,532 (of the respective connector) into a low-power mode and/or forenabling the magnetic coupling unit (of the respective connector), if adevice is detected to be proximate to the cable unit, and for switchingthe data transmission unit (of the respective connector) into ahigh-power mode and/or for disabling the magnetic coupling unit (of therespective connector), if no device is detected to be proximate to thecable unit. Such a proximity detector and control unit may also be usedin other embodiments of the connector and in other devices disclosedherein.

Various methods of proximity detection may be used, e.g. received signalstrength indication (RSSI) methods such as standard Bluetooth, BluetoothLow Energy (BTLE) and Wi-Fi. Other example methods of proximitydetection include differential methods such as ultra-wideband (UWB),optical methods using at e.g. infrared (IR) wavelengths ultrasound andNFC. Proximity detection methods such as IRDA, UWB and NFC typically useboth standard and proprietary data transport mechanisms. In examples,proximity detection may occur when two devices are e.g. within a rangeof 0.5 mm+/−0.1 mm of each other, whereby other distances may be used.

Generally, direct or indirect means for detecting proximity of thedevice to another device may be used. The actual distance between twodevices that can be detected as “proximate” depends e.g. on the magneticdesign; one criterion may be if the magnetic coupling is larger than 90%or preferably larger than 95%, or ultimately larger than 99%. In anexemplary design a magnetic distance of ˜0.5 mm+100 μm (due to 2*0.25 mmplastic housing) is used, which may be understood as “close proximity”.However, other distances may be used instead, depending on theparticular design and/or application.

Finally, within each housing 523, 533 a second connector 540, 550 may bearranged for simultaneously transmitting data to and/or receiving datafrom two devices and/or for simultaneously transmitting power to and/orreceiving power from two devices. Said second connectors 540, 550 aregenerally configured in the same way as the first connectors 520, 530.

The proposed cable units may be used for mutually connecting measurementmodules and monitoring devices. Daisy chains as well as starconfigurations, as shown in FIGS. 20A and 20C are possible. Cables unitsmay be coupled laterally or vertically, on top of each other or with athird component in between. Alternatively, a distribution cable unit mayhave multiple branches to connect components physically.

In the following the pairing of devices will be explained as proposed bythe present invention.

A first option of pairing is to perform pairing manually, e.g. duringthe attachment of a measurement module to a person's body. By bringing adevice physically in close proximity with another, identifiers areexchanged, which effectively means that said device is added into thenetwork of devices, e.g. into the patient network. This is easy toachieve during first time attachment of the measurement module and formobile patients.

The order of connecting is generally not important; every member of thenetwork can communicate and update the network status, e.g. via a masterdevice in particular standards, like Bluetooth-LE. Visual or audibleinformation on the devices may indicate its connection status. It maye.g. indicate which devices are paired into a patient network, and itmay indicate loss of RF connectivity to a hospital network or patientmonitor of e.g. a mobile patient. In such a case the patient networkneeds to (automatically or manually) re-connect to another radio link.

The association mechanism starts when two conditions are met:

-   1. An increased level of magnetic coupling, which can be detected    from the induced voltage in the secondary coil as well as the    current in the primary coil or the resonance frequency of the    assembly. When this condition is met, the RF radios start    communicating with each other (could be via the master device).-   2. When the strengths of the received RF signals are also above a    pre-determined level, associating is started. Alternatively,    deviating transmitter antenna impedance (voltage standing wave ratio    VSWR, reflected waves) can be included as an extra check, indicating    RF absorption of the transmitted signal.

Repeating this mechanism toggles the membership of a patient network,i.e. the master device knows all devices in the network of the specificpatient; it switches between joining and leaving. Network membership maybe shown by visual, tactile or audible actuators (e.g. LED, display,buzzer, beeper, vibrator, etc.). Additionally, a mechanical switch orkeyboard code may be used to force leaving the network.

The patient may have plasters comprising patient-network functionalityas extra identification- and localisation means, to enforce that ameasurement (or sensor) is attached on the correct position on thecorrect patient.

A second option of pairing is to connect immobilized (e.g. OR or ICU)patients to a patient network by use of a cable unit 500 as shown inFIG. 31. By connecting the cable unit between a measurement module and amonitoring device for a short time, the magnetic coupling and the RFamplitude will increase above a certain level, which triggers thepairing mechanism.

A third option of pairing is to use a contactless storage module, whichmay be used as an intermediate storage container to transfer identifiersbetween components in the patient network. This is illustrated in FIG.34 showing a schematic diagram of a fifth embodiment of a system 14according to the present invention comprising a storage module 95. Bybringing the contactless storage module 95 in close proximity of anothercomponent 20 or 30 having a counterpart connector the identifiers areinterchanged and used to update the patient network. An additionalmechanical push button or proximity detector may be used to triggerexchange. Preferably, only one identifier can be stored and transferredto avoid unambiguity.

The contactless storage module 95 can have the form-factor of a pencil,a smart-card or a small box like the measurement modules. Like otherdevices comprising a connector according to the present invention, itcomprises, besides a storage element 98, a magnetic coupling unit 96 anda data transmission unit 97 (e.g. radio hardware) to couple to otherdevices having a counterpart connector.

A fourth option of pairing is to use additional trigger means. A pushbutton or proximity detector (e.g. using optical, magnetic, ultrasoundtechnology) may be added as a condition to initiate the pairing process.Additional trigger means are beneficial as an extra layer of robustnessto omit components to detect the level of coupling (e.g. no RF ormagnetic coupling measurement). Further, in case of a pencil-likedevice, the RF antenna and coil may be located in the tip; the maximumcoupling may be below the predetermined threshold for triggering theassociation process.

A more detailed schematic diagram of a device 600 for wirelesstransmission of data and/or power between the device and another deviceof a system, in particular of a patient monitoring system, is shown inFIG. 37. Said device 600 is configured to apply the above describedapproach for pairing and comprises an identification unit 601 forstoring a unique identifier of the device and a connector 602. Saidconnector 602 comprises a data transmission unit 603 arranged fortransmitting data to and/or receiving data from another device of thesystem having a counterpart connector, a magnetic coupling unit 604 fortransmitting power to and/or receiving power from another device of thesystem having a counterpart connector by use of inductive coupling, anda detection unit 605 for detecting the strength of magnetic couplingbetween the magnetic coupling unit and a magnetic coupling unit of acounterpart connector of another device and for detecting the intensityof data received by the data transmission unit from a data transmissionunit of the other device.

The device 600 further comprises a control unit 606 for controlling thedata transmission unit 603 to transmit the unique identifier of thedevice to the other device and/or to receive the unique identifier ofthe other device, if a) the detected intensity of received data is abovea data intensity threshold and/or its increase is above a data intensityincrease threshold and b) the detected magnetic coupling is above amagnetic coupling threshold and/or its increase is above a magneticcoupling increase threshold.

The device 600 may further comprise a storage unit 607 for storingunique identifiers of other devices received by the data transmissionunit.

The control unit 606 may be configured to control the data transmissionunit to additionally transmit unique identifier of other devices storedin the storage unit and/or to receive unique identifier of otherdevices, if a) the detected intensity of received data is above a dataintensity threshold and/or its increase is above a data intensityincrease threshold and b) the detected magnetic coupling is above amagnetic coupling threshold and/or its increase is above a magneticcoupling increase threshold.

The detection unit 605 may be configured to detect impedance, resonancefrequency and/or induced voltage for detecting the strength of magneticcoupling and/or to detect signal intensity and/or antenna impedance ofan antenna of the data transmission unit for detecting the intensity ofreceived data. The strength of magnetic coupling is often referred to asmagnetic coupling factor k (0<=k<=1).

In case components are already connected, this is clear from theavailability of power and strong RF signal. Attachment of a newcomponent may be detected by use a polling mechanism to check theincrease of magnetic coupling (and, optionally, an RF signal used fordata transmission. Detection of disconnecting components may beperformed by the inverse process: a polling mechanism to measure adecrease of the strength of magnetic coupling by use e.g. of impedance,resonance frequency and/or induced voltage (and, optionally, of the RFsignal). Optionally, the RF signal strength may be measured in addition.

Generally, a first transmission of the unique identifier is interpretedas a request to couple the device with the system and a secondtransmission of the unique identifier is interpreted as a request todecouple the device from the system.

The device may further comprise an indicator 608, in particular avisual, tactile or audible indicator, for indicating the coupling statusof the coupling of the device with the system.

Still further, the device may comprise a user interface 609 for enablinga user to initiate a transmission of the unique identifier or a couplingor decoupling request message.

Still further, the device may comprise a proximity detector 610 fordetecting proximity of the device to the other device, wherein saidcontrol unit is control the data transmission unit the transmit theunique identifier of the device to the other device and/or to receivethe unique identifier of the other device, if additionally proximity ofthe device to the other device is detected. The proximity detector maybe configured as explained above with respect to other embodiments.

The connector 602 and its elements may be configured as explained abovewith respect to other devices and other embodiments. This holdsparticularly for the magnetic coupling unit 604 and for the datatransmission unit 603 which may be configured as disclosed herein, e.g.as shown in any one of FIGS. 10 to 15 or 17 to 28.

Finally, the device 600 may further comprise a data unit 611 forgenerating and/or receiving data, and/or a power unit 612 for supplyingand/or consuming power.

One main advantage of the present invention is that a universal approachis provided that may generally serve all patient monitoringapplications, which is a key factor to achieve in efforts to reducecosts. Further advantages are the modularity and the direct complianceto existing connectivity standards for wireless measurements.

The application of the present invention is not limited to patientmonitoring, but can be extended to mutually isolate modules (sensors,actuators) connected to a common entity in e.g. automotive or cattlebreeding (central milking machines connected to multi-cows). Further,the present invention is not limited to the explicitly disclosed types,forms and numbers of antennas or coils, which are to be understood asexamples only. Components used in the disclosed embodiments may also beconfigured as being compliant with the Qi standard or other wirelesspower standards, and also standard components compliant with the Qistandard may be used for single components according to the presentinvention, if possible from a technical point of view. Further, a devicemay comprise means for vertical and horizontal stacking and includecorresponding coupling means for coupling in the respective direction,i.e. a device may e.g. comprises a combination of the connectors asshown in FIGS. 25A and 26A.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive; theinvention is not limited to the disclosed embodiments. Other variationsto the disclosed embodiments can be understood and effected by thoseskilled in the art in practicing the claimed invention, from a study ofthe drawings, the disclosure, and the appended claims.

In the claims, the word “comprising” does not exclude other elements orsteps, and the indefinite article “a” or “an” does not exclude aplurality. A single element or other unit may fulfill the functions ofseveral items recited in the claims. The mere fact that certain measuresare recited in mutually different dependent claims does not indicatethat a combination of these measures cannot be used to advantage.

Any reference signs in the claims should not be construed as limitingthe scope.

1. A method for enabling a wireless exchange of data and/or powerbetween devices in a system via a cable unit comprising a cable and aconnector arranged at each end of the cable, the connector comprising adata transmission unit and a magnetic coupling unit, the methodcomprising: transmitting data to a device having a counterpart connectorvia the cable unit; and performing at least one of: transmitting powervia the cable unit to another device of the system having a counterpartconnector by use of inductive coupling, and receiving power from anotherdevice of the system having a counterpart connector by use of inductivecoupling.
 2. The method of claim 1, further comprising: simultaneouslytransmitting data to two devices using a second connector arranged atleast at one end of said cable.
 3. The method of claim 1, furthercomprising simultaneously transmitting power to and/or receiving powerfrom two devices using a second connector arranged at least at one endof said cable.
 4. The method of claim 1, further comprising: stackingthe cable unit to other devices having a counterpart connector using ahousing arranged at each end of the cable.
 5. The method of claim 1,further comprising performing at least one of: data processing, dataconversion, and data storage using electronic circuitry.
 6. The methodof claim 1, further comprising: detecting the strength of magneticcoupling between the magnetic coupling unit and a magnetic coupling unitof another devices; and switching the data transmission unit into oneof: (i) a low-power mode if the detected strength of magnetic couplingis above a first threshold and/or has an increase above a secondthreshold, (ii) a high-power mode if the strength of magnetic couplingis below third threshold and/or its decrease is above a fourththreshold, and (iii) a disabled state if the strength of magneticcoupling is below third threshold and/or its decrease is above a fourththreshold.
 7. The method of claim 1, wherein transmitting data isperformed using at least one of: RF transmission, optical transmission,capacitive coupling, and near field communication.
 8. The method ofclaim 1, wherein the connector further comprises a carrier, and whereinthe data transmission unit comprises an RF antenna arranged in or on thecarrier and an RF circuit for driving the RF antenna and/or obtaining RFsignals received by the RF antenna.
 9. The method of claim 1, whereinthe magnetic coupling unit comprises a flux concentrator, and whereinthe method further comprising: concentrating magnetic flux using theflux concentrator and one or more coils arranged around part of the fluxconcentrator.
 10. The method of claim 1, wherein the cable unit furthercomprises a proximity detector and a control unit, wherein the methodfurther comprises: detecting a proximity of the cable unit to anotherdevice using the proximity detector; and performing at least one of:switching the data transmission unit into a low-power mode and/orenabling the magnetic coupling unit, if a device is detected to beproximate to the cable unit, and switching the data transmission unitinto a high-power mode and/or for disabling the magnetic coupling unit,if no device is detected to be proximate to the cable unit.
 11. A methodfor enabling a wireless exchange of data and/or power between devices ina system via a cable unit comprising a cable and a connector arranged ateach end of the cable, the connector comprising a data transmission unitand a magnetic coupling unit, the method comprising: receiving data froma device having a counterpart connector via the cable unit; andperforming at least one of: transmitting power via the cable unit toanother device of the system having a counterpart connector by use ofinductive coupling, and receiving power from another device of thesystem having a counterpart connector by use of inductive coupling. 12.The method of claim 11, further comprising: simultaneously receivingdata to two devices using a second connector arranged at least at oneend of said cable.
 13. The method of claim 11, further comprisingsimultaneously transmitting power to and/or receiving power from twodevices using a second connector arranged at least at one end of saidcable.
 14. The method of claim 11, further comprising: stacking thecable unit to other devices having a counterpart connector using ahousing arranged at each end of the cable.
 15. The method of claim 11,further comprising performing at least one of: data processing, dataconversion, and data storage using electronic circuitry.
 16. The methodof claim 11, further comprising: detecting the strength of magneticcoupling between the magnetic coupling unit and a magnetic coupling unitof another devices; and switching data transmission unit into one of:(i) a low-power mode if the detected strength of magnetic coupling isabove a first threshold and/or has an increase above a second threshold,(ii) a high-power mode if the strength of magnetic coupling is belowthird threshold and/or its decrease is above a fourth threshold, and(iii) a disabled state if the strength of magnetic coupling is belowthird threshold and/or its decrease is above a fourth threshold.
 17. Themethod of claim 11, wherein receiving data is performed using at leastone of: RF transmission, optical transmission, capacitive coupling, andnear field communication.
 18. The method of claim 11, wherein theconnector further comprises a carrier, and wherein the data transmissionunit comprises an RF antenna arranged in or on the carrier and an RFcircuit for driving the RF antenna and/or obtaining RF signals receivedby the RF antenna.
 19. The method of claim 11, wherein the magneticcoupling unit comprises a flux concentrator, and wherein the methodfurther comprising: concentrating magnetic flux using the fluxconcentrator and one or more coils arranged around part of the fluxconcentrator.
 20. The method of claim 11, wherein the cable unit furthercomprises a proximity detector and a control unit, wherein the methodfurther comprises: detecting a proximity of the cable unit to anotherdevice using the proximity detector; and performing at least one of:switching the data transmission unit into a low-power mode and/orenabling the magnetic coupling unit, if a device is detected to beproximate to the cable unit, and switching the data transmission unitinto a high-power mode and/or for disabling the magnetic coupling unit,if no device is detected to be proximate to the cable unit.